| 摘要 |
A method and a device are specified for measuring the angular deviation of an object with the aid of object-referred targets which are designed as optically structured patterned plates. In this case, digital photoelectric evaluation of an image of the target is undertaken. The information values thus obtained are compared with a reference mark corresponding to the target. The target provided with a defined centre (9) is projected on to a detection plane, held stationary, of a receiving device (3). The target image thereby produced is scanned inside the detection plane with the aid of at least one position-sensitive photoelectric detector which is of the sub-divided type and provided with detection areas (11). The values thus obtained are subjected to a correlation comparison with the values derived from the stored reference mark, as a result of which the deviation of the centre of the target from the optical axis is calculated. In particular, a cross correlation comparison is carried out. In this process, the maximum of the cross correlation is determined and from this the desired angular deviation of the centre (9) of the target from the optical axis of the receiving device is determined. Particular advantage has been found to attach to a target which is designed as a radial pattern having circular sectors composed of alternating light and dark areas (7, 8) which coalesce in the common centre (9), it being the case that the centre angle ... Original abstract incomplete. <IMAGE>
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